1. Squeezed together; jammed.2. Completely filled; stuffed: “I recommend the north shore chowder, chockablock with pieces of seasonal fish” (Charles Monaghan).3. (Nautical) Drawn so close as to have the blocks touching. Used of a ship's hoisting tackle
A place that is chock-a-block is very full of people, things, or vehicles. The small roads are chock-a-block with traffic. = packed. a) completely full of people or things chock-a-block with (chock-a-block (1800-1900), from chock on block; influenced by chock-full)